1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __KERNEL_PRINTK__ 3 #define __KERNEL_PRINTK__ 4 5 #include <stdarg.h> 6 #include <linux/init.h> 7 #include <linux/kern_levels.h> 8 #include <linux/linkage.h> 9 #include <linux/cache.h> 10 11 extern const char linux_banner[]; 12 extern const char linux_proc_banner[]; 13 14 #define PRINTK_MAX_SINGLE_HEADER_LEN 2 15 16 static inline int printk_get_level(const char *buffer) 17 { 18 if (buffer[0] == KERN_SOH_ASCII && buffer[1]) { 19 switch (buffer[1]) { 20 case '0' ... '7': 21 case 'c': /* KERN_CONT */ 22 return buffer[1]; 23 } 24 } 25 return 0; 26 } 27 28 static inline const char *printk_skip_level(const char *buffer) 29 { 30 if (printk_get_level(buffer)) 31 return buffer + 2; 32 33 return buffer; 34 } 35 36 static inline const char *printk_skip_headers(const char *buffer) 37 { 38 while (printk_get_level(buffer)) 39 buffer = printk_skip_level(buffer); 40 41 return buffer; 42 } 43 44 #define CONSOLE_EXT_LOG_MAX 8192 45 46 /* printk's without a loglevel use this.. */ 47 #define MESSAGE_LOGLEVEL_DEFAULT CONFIG_MESSAGE_LOGLEVEL_DEFAULT 48 49 /* We show everything that is MORE important than this.. */ 50 #define CONSOLE_LOGLEVEL_SILENT 0 /* Mum's the word */ 51 #define CONSOLE_LOGLEVEL_MIN 1 /* Minimum loglevel we let people use */ 52 #define CONSOLE_LOGLEVEL_DEBUG 10 /* issue debug messages */ 53 #define CONSOLE_LOGLEVEL_MOTORMOUTH 15 /* You can't shut this one up */ 54 55 /* 56 * Default used to be hard-coded at 7, quiet used to be hardcoded at 4, 57 * we're now allowing both to be set from kernel config. 58 */ 59 #define CONSOLE_LOGLEVEL_DEFAULT CONFIG_CONSOLE_LOGLEVEL_DEFAULT 60 #define CONSOLE_LOGLEVEL_QUIET CONFIG_CONSOLE_LOGLEVEL_QUIET 61 62 extern int console_printk[]; 63 64 #define console_loglevel (console_printk[0]) 65 #define default_message_loglevel (console_printk[1]) 66 #define minimum_console_loglevel (console_printk[2]) 67 #define default_console_loglevel (console_printk[3]) 68 69 static inline void console_silent(void) 70 { 71 console_loglevel = CONSOLE_LOGLEVEL_SILENT; 72 } 73 74 static inline void console_verbose(void) 75 { 76 if (console_loglevel) 77 console_loglevel = CONSOLE_LOGLEVEL_MOTORMOUTH; 78 } 79 80 /* strlen("ratelimit") + 1 */ 81 #define DEVKMSG_STR_MAX_SIZE 10 82 extern char devkmsg_log_str[]; 83 struct ctl_table; 84 85 extern int suppress_printk; 86 87 struct va_format { 88 const char *fmt; 89 va_list *va; 90 }; 91 92 /* 93 * FW_BUG 94 * Add this to a message where you are sure the firmware is buggy or behaves 95 * really stupid or out of spec. Be aware that the responsible BIOS developer 96 * should be able to fix this issue or at least get a concrete idea of the 97 * problem by reading your message without the need of looking at the kernel 98 * code. 99 * 100 * Use it for definite and high priority BIOS bugs. 101 * 102 * FW_WARN 103 * Use it for not that clear (e.g. could the kernel messed up things already?) 104 * and medium priority BIOS bugs. 105 * 106 * FW_INFO 107 * Use this one if you want to tell the user or vendor about something 108 * suspicious, but generally harmless related to the firmware. 109 * 110 * Use it for information or very low priority BIOS bugs. 111 */ 112 #define FW_BUG "[Firmware Bug]: " 113 #define FW_WARN "[Firmware Warn]: " 114 #define FW_INFO "[Firmware Info]: " 115 116 /* 117 * HW_ERR 118 * Add this to a message for hardware errors, so that user can report 119 * it to hardware vendor instead of LKML or software vendor. 120 */ 121 #define HW_ERR "[Hardware Error]: " 122 123 /* 124 * DEPRECATED 125 * Add this to a message whenever you want to warn user space about the use 126 * of a deprecated aspect of an API so they can stop using it 127 */ 128 #define DEPRECATED "[Deprecated]: " 129 130 /* 131 * Dummy printk for disabled debugging statements to use whilst maintaining 132 * gcc's format checking. 133 */ 134 #define no_printk(fmt, ...) \ 135 ({ \ 136 if (0) \ 137 printk(fmt, ##__VA_ARGS__); \ 138 0; \ 139 }) 140 141 #ifdef CONFIG_EARLY_PRINTK 142 extern asmlinkage __printf(1, 2) 143 void early_printk(const char *fmt, ...); 144 #else 145 static inline __printf(1, 2) __cold 146 void early_printk(const char *s, ...) { } 147 #endif 148 149 #ifdef CONFIG_PRINTK_NMI 150 extern void printk_nmi_enter(void); 151 extern void printk_nmi_exit(void); 152 extern void printk_nmi_direct_enter(void); 153 extern void printk_nmi_direct_exit(void); 154 #else 155 static inline void printk_nmi_enter(void) { } 156 static inline void printk_nmi_exit(void) { } 157 static inline void printk_nmi_direct_enter(void) { } 158 static inline void printk_nmi_direct_exit(void) { } 159 #endif /* PRINTK_NMI */ 160 161 #ifdef CONFIG_PRINTK 162 asmlinkage __printf(5, 0) 163 int vprintk_emit(int facility, int level, 164 const char *dict, size_t dictlen, 165 const char *fmt, va_list args); 166 167 asmlinkage __printf(1, 0) 168 int vprintk(const char *fmt, va_list args); 169 170 asmlinkage __printf(1, 2) __cold 171 int printk(const char *fmt, ...); 172 173 /* 174 * Special printk facility for scheduler/timekeeping use only, _DO_NOT_USE_ ! 175 */ 176 __printf(1, 2) __cold int printk_deferred(const char *fmt, ...); 177 178 /* 179 * Please don't use printk_ratelimit(), because it shares ratelimiting state 180 * with all other unrelated printk_ratelimit() callsites. Instead use 181 * printk_ratelimited() or plain old __ratelimit(). 182 */ 183 extern int __printk_ratelimit(const char *func); 184 #define printk_ratelimit() __printk_ratelimit(__func__) 185 extern bool printk_timed_ratelimit(unsigned long *caller_jiffies, 186 unsigned int interval_msec); 187 188 extern int printk_delay_msec; 189 extern int dmesg_restrict; 190 191 extern int 192 devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write, void __user *buf, 193 size_t *lenp, loff_t *ppos); 194 195 extern void wake_up_klogd(void); 196 197 char *log_buf_addr_get(void); 198 u32 log_buf_len_get(void); 199 void log_buf_vmcoreinfo_setup(void); 200 void __init setup_log_buf(int early); 201 __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...); 202 void dump_stack_print_info(const char *log_lvl); 203 void show_regs_print_info(const char *log_lvl); 204 extern asmlinkage void dump_stack(void) __cold; 205 extern void printk_safe_init(void); 206 extern void printk_safe_flush(void); 207 extern void printk_safe_flush_on_panic(void); 208 #else 209 static inline __printf(1, 0) 210 int vprintk(const char *s, va_list args) 211 { 212 return 0; 213 } 214 static inline __printf(1, 2) __cold 215 int printk(const char *s, ...) 216 { 217 return 0; 218 } 219 static inline __printf(1, 2) __cold 220 int printk_deferred(const char *s, ...) 221 { 222 return 0; 223 } 224 static inline int printk_ratelimit(void) 225 { 226 return 0; 227 } 228 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, 229 unsigned int interval_msec) 230 { 231 return false; 232 } 233 234 static inline void wake_up_klogd(void) 235 { 236 } 237 238 static inline char *log_buf_addr_get(void) 239 { 240 return NULL; 241 } 242 243 static inline u32 log_buf_len_get(void) 244 { 245 return 0; 246 } 247 248 static inline void log_buf_vmcoreinfo_setup(void) 249 { 250 } 251 252 static inline void setup_log_buf(int early) 253 { 254 } 255 256 static inline __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...) 257 { 258 } 259 260 static inline void dump_stack_print_info(const char *log_lvl) 261 { 262 } 263 264 static inline void show_regs_print_info(const char *log_lvl) 265 { 266 } 267 268 static inline void dump_stack(void) 269 { 270 } 271 272 static inline void printk_safe_init(void) 273 { 274 } 275 276 static inline void printk_safe_flush(void) 277 { 278 } 279 280 static inline void printk_safe_flush_on_panic(void) 281 { 282 } 283 #endif 284 285 extern int kptr_restrict; 286 287 #ifndef pr_fmt 288 #define pr_fmt(fmt) fmt 289 #endif 290 291 /* 292 * These can be used to print at the various log levels. 293 * All of these will print unconditionally, although note that pr_debug() 294 * and other debug macros are compiled out unless either DEBUG is defined 295 * or CONFIG_DYNAMIC_DEBUG is set. 296 */ 297 #define pr_emerg(fmt, ...) \ 298 printk(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 299 #define pr_alert(fmt, ...) \ 300 printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 301 #define pr_crit(fmt, ...) \ 302 printk(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 303 #define pr_err(fmt, ...) \ 304 printk(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 305 #define pr_warn(fmt, ...) \ 306 printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 307 #define pr_notice(fmt, ...) \ 308 printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 309 #define pr_info(fmt, ...) \ 310 printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 311 /* 312 * Like KERN_CONT, pr_cont() should only be used when continuing 313 * a line with no newline ('\n') enclosed. Otherwise it defaults 314 * back to KERN_DEFAULT. 315 */ 316 #define pr_cont(fmt, ...) \ 317 printk(KERN_CONT fmt, ##__VA_ARGS__) 318 319 /* pr_devel() should produce zero code unless DEBUG is defined */ 320 #ifdef DEBUG 321 #define pr_devel(fmt, ...) \ 322 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 323 #else 324 #define pr_devel(fmt, ...) \ 325 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 326 #endif 327 328 329 /* If you are writing a driver, please use dev_dbg instead */ 330 #if defined(CONFIG_DYNAMIC_DEBUG) 331 #include <linux/dynamic_debug.h> 332 333 /* dynamic_pr_debug() uses pr_fmt() internally so we don't need it here */ 334 #define pr_debug(fmt, ...) \ 335 dynamic_pr_debug(fmt, ##__VA_ARGS__) 336 #elif defined(DEBUG) 337 #define pr_debug(fmt, ...) \ 338 printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 339 #else 340 #define pr_debug(fmt, ...) \ 341 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 342 #endif 343 344 /* 345 * Print a one-time message (analogous to WARN_ONCE() et al): 346 */ 347 348 #ifdef CONFIG_PRINTK 349 #define printk_once(fmt, ...) \ 350 ({ \ 351 static bool __section(.data.once) __print_once; \ 352 bool __ret_print_once = !__print_once; \ 353 \ 354 if (!__print_once) { \ 355 __print_once = true; \ 356 printk(fmt, ##__VA_ARGS__); \ 357 } \ 358 unlikely(__ret_print_once); \ 359 }) 360 #define printk_deferred_once(fmt, ...) \ 361 ({ \ 362 static bool __section(.data.once) __print_once; \ 363 bool __ret_print_once = !__print_once; \ 364 \ 365 if (!__print_once) { \ 366 __print_once = true; \ 367 printk_deferred(fmt, ##__VA_ARGS__); \ 368 } \ 369 unlikely(__ret_print_once); \ 370 }) 371 #else 372 #define printk_once(fmt, ...) \ 373 no_printk(fmt, ##__VA_ARGS__) 374 #define printk_deferred_once(fmt, ...) \ 375 no_printk(fmt, ##__VA_ARGS__) 376 #endif 377 378 #define pr_emerg_once(fmt, ...) \ 379 printk_once(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 380 #define pr_alert_once(fmt, ...) \ 381 printk_once(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 382 #define pr_crit_once(fmt, ...) \ 383 printk_once(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 384 #define pr_err_once(fmt, ...) \ 385 printk_once(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 386 #define pr_warn_once(fmt, ...) \ 387 printk_once(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 388 #define pr_notice_once(fmt, ...) \ 389 printk_once(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 390 #define pr_info_once(fmt, ...) \ 391 printk_once(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 392 #define pr_cont_once(fmt, ...) \ 393 printk_once(KERN_CONT pr_fmt(fmt), ##__VA_ARGS__) 394 395 #if defined(DEBUG) 396 #define pr_devel_once(fmt, ...) \ 397 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 398 #else 399 #define pr_devel_once(fmt, ...) \ 400 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 401 #endif 402 403 /* If you are writing a driver, please use dev_dbg instead */ 404 #if defined(DEBUG) 405 #define pr_debug_once(fmt, ...) \ 406 printk_once(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 407 #else 408 #define pr_debug_once(fmt, ...) \ 409 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 410 #endif 411 412 /* 413 * ratelimited messages with local ratelimit_state, 414 * no local ratelimit_state used in the !PRINTK case 415 */ 416 #ifdef CONFIG_PRINTK 417 #define printk_ratelimited(fmt, ...) \ 418 ({ \ 419 static DEFINE_RATELIMIT_STATE(_rs, \ 420 DEFAULT_RATELIMIT_INTERVAL, \ 421 DEFAULT_RATELIMIT_BURST); \ 422 \ 423 if (__ratelimit(&_rs)) \ 424 printk(fmt, ##__VA_ARGS__); \ 425 }) 426 #else 427 #define printk_ratelimited(fmt, ...) \ 428 no_printk(fmt, ##__VA_ARGS__) 429 #endif 430 431 #define pr_emerg_ratelimited(fmt, ...) \ 432 printk_ratelimited(KERN_EMERG pr_fmt(fmt), ##__VA_ARGS__) 433 #define pr_alert_ratelimited(fmt, ...) \ 434 printk_ratelimited(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__) 435 #define pr_crit_ratelimited(fmt, ...) \ 436 printk_ratelimited(KERN_CRIT pr_fmt(fmt), ##__VA_ARGS__) 437 #define pr_err_ratelimited(fmt, ...) \ 438 printk_ratelimited(KERN_ERR pr_fmt(fmt), ##__VA_ARGS__) 439 #define pr_warn_ratelimited(fmt, ...) \ 440 printk_ratelimited(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__) 441 #define pr_notice_ratelimited(fmt, ...) \ 442 printk_ratelimited(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__) 443 #define pr_info_ratelimited(fmt, ...) \ 444 printk_ratelimited(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) 445 /* no pr_cont_ratelimited, don't do that... */ 446 447 #if defined(DEBUG) 448 #define pr_devel_ratelimited(fmt, ...) \ 449 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 450 #else 451 #define pr_devel_ratelimited(fmt, ...) \ 452 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 453 #endif 454 455 /* If you are writing a driver, please use dev_dbg instead */ 456 #if defined(CONFIG_DYNAMIC_DEBUG) 457 /* descriptor check is first to prevent flooding with "callbacks suppressed" */ 458 #define pr_debug_ratelimited(fmt, ...) \ 459 do { \ 460 static DEFINE_RATELIMIT_STATE(_rs, \ 461 DEFAULT_RATELIMIT_INTERVAL, \ 462 DEFAULT_RATELIMIT_BURST); \ 463 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, pr_fmt(fmt)); \ 464 if (DYNAMIC_DEBUG_BRANCH(descriptor) && \ 465 __ratelimit(&_rs)) \ 466 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), ##__VA_ARGS__); \ 467 } while (0) 468 #elif defined(DEBUG) 469 #define pr_debug_ratelimited(fmt, ...) \ 470 printk_ratelimited(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 471 #else 472 #define pr_debug_ratelimited(fmt, ...) \ 473 no_printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__) 474 #endif 475 476 extern const struct file_operations kmsg_fops; 477 478 enum { 479 DUMP_PREFIX_NONE, 480 DUMP_PREFIX_ADDRESS, 481 DUMP_PREFIX_OFFSET 482 }; 483 extern int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, 484 int groupsize, char *linebuf, size_t linebuflen, 485 bool ascii); 486 #ifdef CONFIG_PRINTK 487 extern void print_hex_dump(const char *level, const char *prefix_str, 488 int prefix_type, int rowsize, int groupsize, 489 const void *buf, size_t len, bool ascii); 490 #else 491 static inline void print_hex_dump(const char *level, const char *prefix_str, 492 int prefix_type, int rowsize, int groupsize, 493 const void *buf, size_t len, bool ascii) 494 { 495 } 496 static inline void print_hex_dump_bytes(const char *prefix_str, int prefix_type, 497 const void *buf, size_t len) 498 { 499 } 500 501 #endif 502 503 #if defined(CONFIG_DYNAMIC_DEBUG) 504 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \ 505 groupsize, buf, len, ascii) \ 506 dynamic_hex_dump(prefix_str, prefix_type, rowsize, \ 507 groupsize, buf, len, ascii) 508 #elif defined(DEBUG) 509 #define print_hex_dump_debug(prefix_str, prefix_type, rowsize, \ 510 groupsize, buf, len, ascii) \ 511 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, rowsize, \ 512 groupsize, buf, len, ascii) 513 #else 514 static inline void print_hex_dump_debug(const char *prefix_str, int prefix_type, 515 int rowsize, int groupsize, 516 const void *buf, size_t len, bool ascii) 517 { 518 } 519 #endif 520 521 /** 522 * print_hex_dump_bytes - shorthand form of print_hex_dump() with default params 523 * @prefix_str: string to prefix each line with; 524 * caller supplies trailing spaces for alignment if desired 525 * @prefix_type: controls whether prefix of an offset, address, or none 526 * is printed (%DUMP_PREFIX_OFFSET, %DUMP_PREFIX_ADDRESS, %DUMP_PREFIX_NONE) 527 * @buf: data blob to dump 528 * @len: number of bytes in the @buf 529 * 530 * Calls print_hex_dump(), with log level of KERN_DEBUG, 531 * rowsize of 16, groupsize of 1, and ASCII output included. 532 */ 533 #define print_hex_dump_bytes(prefix_str, prefix_type, buf, len) \ 534 print_hex_dump_debug(prefix_str, prefix_type, 16, 1, buf, len, true) 535 536 #endif 537